iRule for IE8

There is an articular which depicts a way to insert the code ito page to inform a client to upgrade. I suppose the same can be done to insert a piece of code based on it detecting IE8

 

 

Click here to see if this can help you come up with a game plan

 

 

Hope this helps

 

CB

 

Looks to me like the above config is for IIS and is just creating a custom response header for all requests. If you want to add this to all requests, regardless of the browser, it would be as simple as this:

when HTTP_RESPONSE {   
   HTTP::header insert "X-UA-Compatible" "IE=EmulateIE7"   
 }

If you want to only do this for IE8 browsers, you'll need to add a HTTP_REQUEST event and look at the value of [HTTP::header User-Agent] and if that matches IE8 (I don't have that value handy), then you could set a value that is read in the HTTP_RESPONSE to determine whether the header is added.

You also, might want to check if the header already exists in the response and only add it if it's not there already.

when HTTP_RESPONSE {   
   if { ! [HTTP::header exists "X-UA-Compatible"] } {   
     HTTP::header insert "X-UA-Compatible" "IE=EmulateIE7"   
   }   
 }

But, based on the config above, it's globally setting the header for all responses to the above iRule should work for you.

Let us know if this works out for you.

-Joe

Thanks for replies. Will let you know how it goes

Doh! Don't write iRules for a few weeks and see what happens. Thanks for the catch hoolio!

 

 

*Reply above has been corrected.

 

 

-Joe

I have been working on a rule to do this but it does not quite work. Any ideas?

 

 

 

reference sites

 

1) http://msdn.microsoft.com/en-us/library/cc817582.aspx

 

2) http://msdn.microsoft.com/en-us/library/cc817570.aspx

 

 

rule IE8Fix {

 

when RULE_INIT {

 

set ::IE8Resp 0

 

}

 

 

when HTTP_REQUEST {

 

if { [regexp {"MSIE ([0-9]{1,}[\.0-9]{0,})"} [HTTP::header User-Agent] origUA UAVer ] } {

 

switch $UAVer {

 

"8.0" {

 

set ::IE8Resp 1

 

log "[IP::client_addr]:[TCP::client_port] IE 8 detected"

 

}

 

"7.0" {

 

set ::IE8Resp 0

 

log "[IP::client_addr]:[TCP::client_port] IE 7 detected"

 

}

 

default {

 

log "[IP::client_addr]:[TCP::client_port] IE $UAVer detected"

 

}

 

}

 

}

 

}

 

 

when HTTP_RESPONSE {

 

if { $::IE8Resp } {

 

todo, make sure the header insert format is right

 

log "[IP::client_addr]:[TCP::client_port] inserting header"

 

HTTP::header insert "X-UA-Compatible" "IE=EmulateIE7"

 

}

 

}

 

}

 

 

I was trying to make it only trigger when the browser was IE8...

 

 

Is my impression that the entire rule ( eg, http_request, http_response, rule_init ) execute on a per-request/response pair or is that not the case?

A global variable will be accessible and changeable across all TCP connections. You'd want to use a local variable so that it's only accessible across a single TCP connection.

With that said, I don't think there is any reason to check whether to insert the response header or not. Just insert it in every response and non-IE8 browsers will ignore it.

If you do want to check the User-Agent header before setting the custom X-UA-Compatible header in the response, you could do something like this. Note, as Joe always says, you should use string operations instead of regexes whenever possible to save CPU cycles/memory.

 
 when HTTP_REQUEST { 
  
     Check if User-Agent header is IE 8 
    if { [HTTP::header User-Agent] contains "MSIE 8" } { 
       set IE8Resp 1 
    } else  { 
       set IE8Resp 0 
    } 
 } 
 when HTTP_RESPONSE { 
  
    if { $IE8Resp } { 
  
       log "[IP::client_addr]:[TCP::client_port] inserting header" 
       HTTP::header insert "X-UA-Compatible" "IE=EmulateIE7" 
    } 
 } 
 

Aaron

Yea that makes sense on the regexp - good point. Thanks!

Posted By hoolio on 03/25/2009 9:14 AM

 

...Note, as Joe always says, you should use string operations instead of regexes whenever possible to save CPU cycles/memory.

 

 

 

Amen brother!

 

 

-Joe

 

This should be uploaded in the samples

Hey cmbhatt, it's a wiki, so you could add it too :D. Here you go:

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/Emulate_IE7_header_insertion_in_response_for_IE8.html (Click here)

 

 

Aaron